ASSEMBLY FOR PLACING A PROSTHETIC VALVE IN A DUCT IN THE BODY

• US 20080215143A1
• Filed: 07/27/2007
• Published: 09/04/2008
• Est. Priority Date: 07/04/2001
• Status: Active Grant

• Current Assignee: Medtronic CV Luxembourg SARL (Medtronic Plc)
• Original Assignee: Medtronic Corevalve LLC (Medtronic Plc)
• Inventors: Seguin, Jacques
• Granted Patent: US 7,780,726 B2
• Time in Patent Office: Days
• US Class Current: 623/2.17
• CPC Class Codes: A61F 2/2403 with pivoting rigid closure members check valves with hinged closure members in general F16K15/03
• CPC Class Codes: A61F 2/2418 Scaffolds therefor, e.g. support stents
• CPC Class Codes: A61F 2220/0008 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2220/0016 with sharp anchoring protrusions, e.g. barbs, pins, spikes
• CPC Class Codes: A61F 2220/005 using adhesives
• CPC Class Codes: A61F 2230/0067 conical
• CPC Class Codes: A61F 2250/006 modular

Abstract

The present invention is an assembly comprising a prosthetic valve to be implanted; a radially expandable stent comprising at least one zone intended to be expanded to allow the stent, in the expanded state, to bear against the wall of the body duct to be fitted with the valve, this bearing making it possible to immobilize this stent with respect to this wall; and means for mounting the valve with respect to the stent, making it possible to connect the valve to the stent in such a way that the placement of the stent allows the valve to be mounted in the body duct, and expansion means such as a balloon catheter being provided to trigger expansion of the stent at the implantation site. According to the invention, the valve and the stent are designed in such a way that, at the moment when the stent is expanded, the valve is situated outside the zone or zones of the stent that are subjected to said expansion means. The invention thus consists in separating the valve and said zone or zones to be expanded, so that the expansion of the stent can be effected with an expansion force suitable for perfect anchoring of this stent in the wall of the body duct to be fitted with the valve, and without any risk of destruction or damage of the valve.

Claims

1. A prosthetic valve assembly comprising:

an implantable prosthetic valve;

a radially expandable stent comprising at least one expandable zone that is configured, in an expanded state, to bear against a wall of the native body lumen in a manner so as to resist migration; and

means for mounting the valve on the stent such that, when expanded, the valve is positioned outside of the zone.

2. The assembly of claim 1, further comprising expansion means to expand at least the zone of the stent at the desired implantation site.

3. The assembly of claim 1, where in the stent is mounted within a second zone distinct from the first zone.

4. The assembly of claim 3, wherein the mounting means comprises conduits on a peripheral wall of the valve and arms arranged on the stent, the peripheral wall of the valve configured to engage and slide on the arms.

5. The assembly of claim 1, wherein the mounting means is configured such that the valve is axially movable with respect to the stent between a position of non-implantation outside the first zone to be expanded, and a position of implantation, which it can reach after expansion of the stent, in which it is immobilized axially with respect to the stent.

6. The assembly of claim 5, wherein the mounting means comprises radially positioned fastening members mounted on the valve configured to be inserted into the body wall.

7. The assembly of claim 6, wherein the fastening member are configured to insert into the body upon a pivoting of the valve about its axis.

8. The assembly of claim 6, wherein the fastening member are configured to insert into the body upon a longitudinal movement of the valve with respect to the stent.

9. The assembly of claim 6, wherein the fastening members comprise spikes, hooks or claws.

10. The assembly of claim 5, wherein the mounting means comprises burstable vesicles.

11. The assembly of claim 10, wherein the vesicles are filled with adhesive.

12. The assembly of claim 11, wherein the vesicles are configured to burst when the valve is brought into its position of implantation.

13. The assembly of claim 5, wherein the mounting means comprises at least one band integrated in the peripheral wall of the valve and having a shape memory, so that it keeps the valve pressed against the stent in the position of implantation of this valve.

14. The assembly of claim 13, wherein the band comprises a wire.

15. The assembly of claim 13, wherein the band is circular in shape.

16. The assembly of claim 13, wherein the band is helical in shape.

17. The assembly of claim 5, wherein the mounting means comprises conduits.

18. The assembly of claim 17, further comprising rods configured to engage and slide through the conduits as the valve moves from its position of non-implantation to its position of implantation.

19. The assembly of claim 18, further comprising means to immobilize the conduits with respect to the rods in the position of implantation.

20. The assembly of claim 19, further comprising wires connected to the rods and configured to pass through said conduits to guide said rods in the conduits.

21. The assembly of claim 1, wherein the mounting means is configured such that, beyond a threshold of expansion of the stent, said means permits a different amount of expansion of the valve and the stent, whereby the variation in the degree of expansion of the stent does not substantially impact the degree of expansion of the valve.

22. The assembly of claim 1, further comprising means for limiting the expansion of the valve.

23. The assembly of claim 1, wherein the valve comprises a peripheral wall with a tapered diameter in the axial direction and the zone of the stent supporting the valve has a corresponding shape.

24. The assembly of claim 1, wherein the the stent comprises a middle portion having a smaller diameter than at end portions thereof, the valve having a shape corresponding to that zone of the stent in whose area it is intended to be mounted.

25. The assembly of claim 24, wherein the middle portion forms two inverted truncated cones.

26. The assembly of claim 24, wherein the middle portion forms an hourglass shape.

27. The assembly of claim 1, wherein the valve has a peripheral wall and the stent has, in the distal continuation of that zone of the stent intended to receive the valve, a foldable portion movable between an extended position, in which it is situated in the distal continuation of said zone, and a folded position, in which it is placed against the inner face of the peripheral wall of the valve, and traps this peripheral wall between it and said zone of the stent.

28. The assembly of claim 27, further comprising retaining means for keeping this foldable portion in a folded position.

29. The assembly of claim 28, characterized in that said retaining means are formed by a wire (46) made of a material which is rigid but has a degree of elastic flexibility, for example a metal material having an undulated form and extending over the entire circumference of said foldable portion (45).

30. The assembly of claim 1, further comprising a sheath that comprises an impermeable biocompatible material and at least partially covers the stent.

32. The assembly of claim 27, further comprising a sheath that comprises an impermeable biocompatible material and at least partially covers the stent.

33. The assembly of claim 32, wherein the foldable portion is formed by a continuation of the sheath forming a sleeve beyond the zone of the stent intended to receive the valve.

34. The assembly of claim 30, further comprising an inflatable peripheral chamber configured to be inflated so as to substantially form a seal between the stent and the wall of the body lumen to be fitted with the valve.

35. The assembly of claim 34, comprising a plurality of inflatable peripheral chambers positioned radially on the portion of the stent intended to bear against the native cardiac valvular ring.

36. The assembly of claim 1, wherein the stent comprises a cylindrical portion that is configured to bear against the native cardiac valvular ring and a distal portion connected to the cylindrical portion.

37. The assembly of claim 1, wherein the the stent comprises a tapered proximal portion whose diameter decreases in the distal direction and is configured to, upon implantation, to bear against the wall of the ventricle or corresponding auricle of the heart.

38. The assembly of claim 37, further comprising a supplementary bearing portion on the stent connected by rods to the distal portion or to the cylindrical portion, the rods configured of sufficient length so that, when implanted, the supplementary bearing portion is positioned beyond the coronary ostia.

39. The assembly of claim 1, further comprising retractable hooks on the stent to minimize migration.

40. The assembly of claim 1, wherein the stent comprises a portion of high radial force.

31. The assembly of claim 31, wherein the sheath has lateral openings that are configured to be positioned opposite the coronary ostia when implanted.